The influence of corneal astigmatism on retinal nerve fiber layer thickness and optic nerve head parameter measurements by spectral-domain optical coherence tomography.

Abstract

BACKGROUND:

To evaluate the influence of corneal astigmatism (CA) on retinal nerve fiber layer (RNFL) thickness and optic nerve head(ONH) parameters measured with spectral-domain optical coherence tomography (OCT) in high myopes patients before refractive surgery.

METHODS:

Seventy eyes of 35 consecutive refractive surgery candidates were included in this study. The mean age of the subjects was 26.42 ± 6.95 years, the average CA was -1.17 diopters (D; SD 0.64; range -0.2 to-3.3D), All subjects in this study were WTR CA. 34 eyes were in the normal CA group with a mean CA was -0.67 ± 0.28D, 36 eyes were in the high CA group with an average CA of -1.65 ± 0.49D. All subjects underwent ophthalmic examination and imaging with the Cirrus HD OCT.

RESULTS:

No significant difference was noted in the average cup-to-disk ratio, vertical cup-to-disk ratio and cup volume (all P values > 0.05). Compared with the normal CA group, the high CA group had a larger disc area and rim area, thinner RNFL thickness in the temporal quadrant, and the superotemporal and inferotemporal peaks were farther to the temporal horizon (All P values < 0.05). There were no significant differences between the two groups in global average RNFL thickness, as well as superior, nasal and inferior quadrant RNFL thickness (all P values > 0.05).

CONCLUSIONS:

The degree of with-the-rule CA should be considered when interpreting ONH parameters and peripapillary RNFL thickness measured by the Cirrus HD OCT.

VIRTUAL SLIDES:

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1148475676881895.

• Authors: Lin Liu, Jun Zou, Hui Huang, Jian-guo Yang, Shao-rong Chen
• Journal: Diagnostic pathology (Diagn Pathol) Vol. 7 Pg. 55 (May 23 2012) ISSN: 1746-1596 [Electronic] England
• PMID: 22621341 (Publication Type: Journal Article)

Topics

• Adolescent
• Adult
• Astigmatism (diagnosis, pathology, physiopathology, surgery)
• Cornea (pathology, physiopathology)
• Female
• Humans
• Intraocular Pressure
• Male
• Manometry
• Myopia (diagnosis, pathology, physiopathology, surgery)
• Nerve Fibers (pathology)
• Optic Disk (pathology)
• Predictive Value of Tests
• Refraction, Ocular
• Refractive Surgical Procedures
• Retinal Neurons (pathology)
• Tomography, Optical Coherence
• Visual Acuity
• Young Adult